HeidiG!!!!!!!

First of all you have to understand that you need to colonise benneficial bacteria in the filter pad which converts the ammonia into nitrates, much less toxic than ammonia.

You will kill all your fish unless you take this period seriously and DO NOT change the filter pad. That is where the bacteria you need are colonising. Changing it just removes the bacteria and ammonia levels will rise and belly up for the fish.

There is a term called the "cycle" which is the process by which the bacteria in the filter covert ammonia to first nitr(i)tes, and then to Nitr(a)tes. A healthy fish tank has a healthy "cycle" going 24/7 producing nitrates.

Meathods for keeping the cycle alive are to rinse the filter pad in the water you've removed during a water change. Rinsing in the sink can kill the bacteria with the chlorine in tap water. Only change the pad when it's falling apart, and by the way you should have a back up area for the bacteria to live as there are none in a new pad.

This back up area could be a second pad. Change, or rinse the pads at seperte times so the new pad can seed and grow bacteria before you change the second, by rotating pads. Allow at least a week for a new pad to seed before removing and old one.

If your filter has only one pad go and buy a sponge filter (a prefabricated sponge) and slip it onto the filter intake. This will be a second back up place for bacteria to live. This can be removed and rinsed the same way as the pads in non-chlorinated water.

You need to get ammonia levels to absolute ZERO ppm. Then you need to get nitrItes to zero, and finally get nitrates which are much less toxic to fish.

1st feed VERY sparingly during this period. Do 50-75% water changes and don't forget dechlorinator that also dechlorinates chloramines as well as chlorine.

Feeding sparingly will keep ammonia levels from rising too quickly before the bacteria have a chance to eat it, coverting it to nitrites and then nitrates. Water changes will dilute the ammonia untill bacteria grow to large enough numbers to eat up all the ammonia.

There should never be any uneaten food left after feeding. That means you've fed way too much and you need to get that extra food out asap.

Go buy a water test kit that tests ammonia, nitrites, nitrates, and pH, or go have your water tested at the store.

Remember that a healthy tank has zero ammonia, zero nitrites, and less than 20 or so ppm nitrates.

You then need to do water changes enough to keep nitrates at levels I above mentioned.

Stop using chemicals as they're no substitute for a healthy cycle, water changes, and management of a benneficial bacteria colony, and determin the frequency of water changes by doing them enough to keep nitrates at above levels and you'll have a healthy tank.

Also a note about your fish, you have a very nice selection, but just watch the red tail shark, can grow little too big for a crowded 20gal tank and will get aggressive

you have almost the full amount now for your tank, but just get tto know them and watch them when you can as there attitudes may change as they get older and bigger and you may need to up grade your tank to something larger, altho this won't be soon, maybe something to consider and watch for in the future

I hope your levels do drop, the first few weeks of a new tank setup are the worst, especially if your new with little knowledge, but once your passed this, you will find yourself just standing and randomly staring at the tank, it is a great hobby and the work does pay off.

Good luck.

Maybe if it's still wet you could stick it in behind thenew one to help seed it, though there might be different opinions. I only clean mine when they start blocking the water flow.

You have no cycle at this point. This is a critical time and the fish can do fine with very little food at this point. If ammonia gets too high it'll itself kill the bacteria. Food and poop and anything rotting produces ammonia, so by putting as little food into the tank as possible at this point is going to help keep that ammonia spike from getting to critical levels till the cycle establishes itself.

Sounds like you have a handle on understanding what's going on.

Keep us posted, and you may even do water changes daily until the cycle establishes itself. I'd do at least 50% change myself during this period.

Remember, the bacteria are mainly living attatched to surfaces, so you aren't dumping bacteria when you do water changes as some people believe.

Picked the fish out???? Does this man they're all dead now? You need fish in there to produce the food to keep the bacteria alive. (unless you do a fishless cycle. Something a bit more involved and not usually done by most people)

Leave the cartrage in till water peramiters are good, ie the cycle is working and keeping ammonia and nitrites at zero.

With kids that young I'd considder making it a rule to stay out of the tank. You could measure out a tiny bit of food for them so the kids don't feed too much.

Of course it's fun to feed fish, esp for kids. They just don't know that fish are allways going to beg for food and really don't need that much.

You could feed even twice per day, but very little if any should be reaching the bottom before it's eaten.

Cute tank!

You'll get it right soon. You might get a little cloudy water for a day or two and this is a normal part of the bacteria getting adjusted to your tank. One thing I like to do, as well as many others, is to have much more filtration than what is required. You can add a second filter if there's room, or a canister type which goes under the tank and doesn't get in the way of a hang on back (HOB) type. This way you'll have a tank that can tollerate occasional over feeding, over stocking, etc. The sponge is still a good idea too as it also keeps the main filter from clogging up as fast. The sponge does have to be rinsed often, but that's pretty easy. If you have bacteria in other places you can rinse in tap water. Just a suggestion.

I got back into aquariums when my son was about 4. We had a lot of fun with the whole thing. I was into it as a child myself, collecting fish and crayfish from the stream nearby (when I lived in upstate NY). Now I have 5 tanks, with 4 including my 100 gallon in my bedroom. It's a fun hobby, and a lot more fun when you understand the basics and can keep fish alive.

Good luck! PK